A hot and cold water mixing discharge device such as a hot and cold water mixing faucet is used in a place such as a kitchen, a bathroom and a lavatory so that the device can receive a hot and a cold waters at the same time, and mix them together in appropriate quantities to discharge a warm water of appropriate temperature such as about 30.degree. to 45.degree. C. Although such faucets of various constructions are known, typical ones of them are a thermostatic mixing valve unit, a hot and cold water mixing faucet of the single manipulation handle type and so forth. The thermostatic mixing valve unit includes an automatic temperature control section provided in a warm water passage to automatically regulate the ratio of the flow rates of a hot and a cold waters through a temperature sensor to keep the temperature of a mixed warm water at a preset temperature, and an open/close section provided in the body of the unit separately from the former section to start and stop the discharge of the warm water and regulate the flow rate thereof. In the faucet of the single manipulation handle type, a temperature control section and an open/close section are integrally provided so that the sections can be manipulated by horizontally turning and vertically swinging a single handle with the lever thereof.
Since the temperature control section for presetting and regulating the temperature and the open/close section for starting and stopping the discharge of the warm water and regulating the flow rate thereof are provided separately from each other in the thermostatic mixing valve unit, it takes time and trouble to manipulate the unit. When only a warm water of preset temperature is to be always discharged from the unit, the temperature is only once preset by the temperature control section and the open/close section is thereafter manipulated. However, every time a warm water of temperature different from an already preset temperature is to be discharged from the unit, the temperature control section is manipulated again to preset the former temperature replace the latter and the open/close section is thereafter manipulated. For that reason, it is troublesome to manipulate the unit in the latter case.
Since the hot and cold water mixing faucet of the single manipulation handle type does not have a thermostatic function, the temperature of a warm water to be discharged is likely to sharply change due to the change in the pressure of a supplied cold or hot water of the temperature of the hot water after the regulation of the former temperature to give an unpleasant feeling or even cause a scald. Since the faucet does not have a means for enabling the user of the faucet to swing and turn the handle thereof stepwise to precisely set the flow rate and temperature of the warm water at desired levels, the user only depend on his sixth sense for the setting. For that reason, the warm water is likely to be discharged too much or discharged to make intense splashes. Since the regulation of the temperature and flow rate of the discharged warm water and the start and stoppage of the discharge thereof and the regulation can be performed by manipulating the handle with the lever thereof, the manipulating property of the faucet is very high. However, since even a little child can easily move the handle with the lever thereof, he is likely to discharge very hot water from the faucet for fun or by mistake. Besides, a part of a person is likely to unexpectedly come into contact with the handle to move it to discharge very hot water from the faucet.
The present invention was made in consideration of the above-mentioned problems of the prior arts. Accordingly, it is an object of the invention to provide a hot and cold water mixing faucet or a hot and cold water mixing discharge device, which is better in manipulating property than the conventional thermostatic mixing valve unit and higher in the stability of the temperature of discharged water than the conventional hot and cold water mixing faucet of the single manipulation handle type.